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Histrionicotoxins: Roentgen-Ray Analysis of the Novel Allenic and Acetylenic Spiroalkaloids Isolated from a Colombian Frog, <i>Dendrobates histrionicus</i>

Proceedings of the National Academy of SciencesPublished 1 August 1971Open access
John W. Daly, Isabella L. Karle, Charles W. Myers, Takashi Tokuyama, James A. Waters, Bernhard Witkop
Citations181
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TL;DR

The structures and absolute configuration of two unique alkaloids isolated from the Colombian frog, Dendrobates histrionicus and dihydro-isohistrionicotoxin, have been elucidated by Roentgen-ray (x-ray) crystallography.

Abstract

The structures and absolute configuration of two unique alkaloids isolated from the Colombian frog, Dendrobates histrionicus, have been elucidated by Roentgen-ray (x-ray) crystallography. Histrionicotoxin is (2pR, 6S, 7pS, 8aS)-7-(cis-1-buten-3-ynyl)-8-hydroxy-2-(cis-2-penten-4- ynyl)-1-azaspiro[5.5] undecane, while in dihydro-isohistrionicotoxin the acetylenic 2-pentenynyl side chain is replaced by an allenic 2-(3,4 pentadienyl) substituent. Dendrobates histrionicus exhibits remarkable interpopulational variations in amounts and composition of skin toxins, in behavior, and in phenotypic characters, aspects of which are illustrated in a color plate. The histrionico-toxins are the third class of alkaloids isolated from the defensive skin secretions of Neotropical (Dendrobatidae) frogs.

Keywords

Immunology and MicrobiologyAgricultural and Biological SciencesEnvironmental Science